U.S. patent application number 10/196327 was filed with the patent office on 2004-01-22 for system and method for providing partial presence notifications.
Invention is credited to Costa-Requena, Jose, Leppanen, Eva-Maria, Lonnfors, Mikko.
Application Number | 20040015569 10/196327 |
Document ID | / |
Family ID | 30115053 |
Filed Date | 2004-01-22 |
United States Patent
Application |
20040015569 |
Kind Code |
A1 |
Lonnfors, Mikko ; et
al. |
January 22, 2004 |
System and method for providing partial presence notifications
Abstract
A system and method for communicating partial notifications
relating to a presentity's presence information. The communication
may be effected between presence servers and terminals coupled to
the presence servers via a network. At least one presentity is
identified to which a terminal has requested presence services. A
presence document is created, where the presence document includes
presence information corresponding to the presentity. The presence
information is configured as partial presence information
comprising less than a total of the presence information available
for the presentity. The presence document having the partial
presence information is communicated to the terminal requesting the
presence information.
Inventors: |
Lonnfors, Mikko; (Helsinki,
FI) ; Leppanen, Eva-Maria; (Tampere, FI) ;
Costa-Requena, Jose; (Helsinki, FI) |
Correspondence
Address: |
CRAWFORD PLLC
Suite 390
1270 Northland Drive
St. Paul
MN
55120
US
|
Family ID: |
30115053 |
Appl. No.: |
10/196327 |
Filed: |
July 16, 2002 |
Current U.S.
Class: |
709/220 |
Current CPC
Class: |
H04L 65/1016 20130101;
H04L 67/54 20220501; H04L 9/40 20220501; H04L 67/14 20130101; H04W
64/00 20130101; H04L 51/043 20130101; H04L 51/212 20220501; H04W
4/80 20180201; H04W 4/02 20130101; H04L 67/564 20220501; H04L
67/566 20220501; H04L 51/58 20220501; H04W 4/029 20180201; H04W
84/042 20130101; H04L 67/56 20220501; H04L 67/52 20220501; H04L
51/04 20130101 |
Class at
Publication: |
709/220 |
International
Class: |
G06F 015/177 |
Claims
What is claimed is:
1. A method for communicating presence information between presence
servers and terminals coupled to the presence servers via a
network, the method comprising: identifying at least one presentity
to which a terminal has requested presence services; creating a
presence document including presence information corresponding to
the presentity; configuring the presence information as partial
presence information comprising less than a total of the presence
information available for the presentity; and communicating the
presence document having the partial presence information to the
terminal requesting the presence information.
2. The method of claim 1, wherein configuring the presence
information comprises providing status information for presence
information that have changed.
3. The method of claim 1, wherein configuring the presence
information comprises providing a mode value in the presence
information indicative of whether the presence document includes
the partial presence information or a complete update of presence
information.
4. The method of claim 1, wherein configuring the presence
information comprises providing at least one action value in the
presence information.
5. The method of claim 1, wherein creating a presence document
comprises creating a presence document conforming to a Common
Profile for Instant Messaging (CPIM) specification using Presence
Information Data Format (PIDF), and creating an extension to the
CPIM PIDF presence document to facilitate the configuring of the
presence information as partial presence information comprising
less than a total of the presence information available for the
presentity.
6. The method of claim 5, wherein configuring the presence
information comprises providing status information for one or more
presence document tuples that have experienced a status information
change.
7. The method of claim 6, wherein configuring the presence
information further comprises providing a tuple version indicator
corresponding to a new version of the tuple that has experienced
the status information change.
8. The method of claim 6, wherein configuring the presence
information comprises providing at least one action value in the
presence document tuples to identify an action to be taken at the
terminal for the corresponding presence document tuples.
9. The method of claim 5, wherein configuring the presence
information comprises providing a document version indicator to
identify a document version of the presence document, wherein the
document version may be used by the terminal to determine whether
presence information stored at the terminal is synchronized with
the presence server.
10. The method of claim 1, further comprising facilitating terminal
subscription to the presence information of the at least one
presentity.
11. The method of claim 10, wherein facilitating terminal
subscription to the presence information comprises facilitating at
least one of terminal-initiated fetching and terminal-initiated
polling for the presence information.
12. The method of claim 11, wherein facilitating terminal
subscription to the presence information comprises subscribing the
terminal to presence information notifications initiated at the
presence server.
13. The method of claim 12, wherein communicating the presence
document comprises communicating the presence document when at
least some of the presence information has changed.
14. The method of claim 1, further comprising recognizing a change
in at least some of the presence information, and wherein
communicating the presence document comprises communicating the
presence document in response to a presence information change.
15. The method of claim 1, wherein communicating the presence
document comprises communicating the presence document in response
to at least one of an occurrence of a predetermined event, an
occurrence of a predetermined time lapse, and a predetermined
time.
16. The method of claim 1, wherein configuring the presence
information comprises providing at least one predefined attribute
value with the partial presence information.
17. A method for notifying client terminals of presence
information, comprising: (a) creating a presence document for use
by at least one terminal requesting presence information regarding
a presentity, comprising: (i) creating at least one tuple, wherein
the tuple includes a version value indicating a version of the
tuple relative to previous versions of the tuple; (ii) associating
presence information with the tuple, wherein the presence
information comprises a subset of the presentity's complete set of
presence information; (b) sending the presence document to the
client terminal requesting the presence information; (c) comparing
the version value provided via the tuple to a current version value
stored on the client terminal; and (d) directing the client
terminal to update presence information associated with the tuple,
if the version value provided via the tuple indicates new presence
information is available for that tuple.
18. The method of claim 17, wherein creating a presence document
comprises associating the presence information with the tuple if
the presence information changed relative to previous presence
information.
19. The method of claim 17, wherein creating the tuple comprises
including an action element with the tuple to direct the client
terminal to perform a corresponding action upon execution of the
tuple.
20. The method of claim 17, wherein creating the presence document
further comprises creating a document-level version element
including a document-level version value corresponding to a number
of times in which the presence document has been sent to the client
terminal.
21. The method of claim 17, wherein creating the presence document
further comprises creating a mode element including a mode value
indicative of whether the client device should updated with the
subset of the presentity's set of presence information or whether
the client device should be fully updated with the complete set of
presence information.
22. The method of claim 17, wherein creating a presence document
further comprises creating at least one namespace declaration
corresponding to elements associated with the tuple.
23. The method of claim 17, wherein creating a presence document
comprises creating a presence document otherwise conforming to the
Common Profile for Instant Messaging (CPIM) specification using
Presence Information Data Format (PIDF), and wherein creating a
presence document further comprises creating an extension to the
CPIM PIDF presence document to facilitate the configuring of the
presence information as partial presence information comprising
less than a total of the presence information available for the
presentity.
24. A presence awareness system, comprising: (a) at least one
terminal comprising a watcher application that watches for presence
information corresponding to a presentity; (b) at least one
presence server coupled to the at least one terminal via a network,
wherein the presence server comprises a processor configured to:
(i) identify at least one presentity to which the watcher
application has requested presence services; (ii) create a presence
document including the presence information corresponding to the
presentity; (iii) configure the presence information as partial
presence information comprising less than a total of the presence
information available for the presentity; (iv) communicate the
presence document having the partial presence information to the
watcher application of the terminal requesting the presence
information.
25. The presence awareness system as in claim 24, wherein the
network comprises: a presentity presence proxy coupled to the
presence server; a watcher presence proxy coupled to the terminal
and to the presentity presence proxy; and wherein the presentity
presence proxy and watcher presence proxy facilitates the
communication of the presence document and presence information
over the network.
26. A presence server coupled to a plurality of terminals via a
network for communicating presence information to one or more of
the plurality of terminals via the network, the presence server
comprising: a memory configured to store presence information for a
plurality of presentities, and to store terminal subscriptions for
terminals authorized to receive the presence information for one or
more of the presentities; a processing system coupled to the memory
and configured to identify at least one presentity to which a
particular terminal has subscribed, and to create a presence
document including the presence information corresponding to the
presentity, wherein the presence information is configured as
partial presence information corresponding to a subset of a set of
presence information available for the presentity; and a data
transmission module coupled to the processing system to communicate
the partial presence information via the presence document to the
subscribing terminal over the network.
27. The presence server as in claim 26, wherein the processing
system is configured to create the presence document by creating
the presence document conforming to a Common Profile for Instant
Messaging (CPIM) specification using Presence Information Data
Format (PIDF), and by creating an extension to the CPIM PIDF
presence document to facilitate the configuring of the presence
information as the partial presence information.
28. The presence server as in claim 27, wherein the processing
system is configured to create the extension to the CPIM PIDF
presence document by providing status information for one or more
presence document tuples that have experienced a status information
change.
29. The presence server as in claim 28, wherein the processing
system is further configured to provide a tuple version indicator
corresponding to a new version of the tuple that has experienced
the status information change.
30. The presence server as in claim 28, wherein the processing
system is further configured to create the extension to the CPIM
PIDF presence document by providing at least one action value in
the presence document tuples to identify an action to be taken at
the subscribing terminal for the corresponding presence document
tuples.
31. The presence server as in claim 27, wherein the processing
system is configured to create the extension to the CPIM PIDF
presence document by providing a document version indicator to
identify a document version of the presence document, wherein the
document version may be used by the subscribing terminal to
determine whether presence information stored at the subscribing
terminal is synchronized with the presence server.
32. The presence server as in claim 26, wherein the processing
system is configured to create the presence document as partial
presence information by identifying within the presence document
the subset of presence information that has changed relative to the
presence information stored at the subscribing terminal.
Description
FIELD OF THE INVENTION
[0001] This invention relates in general to communications, and
more particularly to a system and method for communicating partial
notifications relating to a presentity's presence information.
BACKGROUND OF THE INVENTION
[0002] Mobile and landline/wireline computing devices have in
recent years become a valuable tool in day-to-day communications.
Desktop computers, workstations, and other wireline computers
currently allow users to communicate via e-mail, video
conferencing, and instant messaging (IM) to name a few
communication applications. Mobile devices, such as mobile
telephones, handheld computers, personal digital assistants (PDAs),
etc. also assist in day-to-day communication. Mobile/wireless
telephones have conventionally served as voice communication
devices, but through technological advancements have recently
proved to be effective devices for communicating data, graphics,
etc. Wireless and landline technologies continue to merge into a
more unified communication system, as user demand for seamless
communications across different platforms increases.
[0003] Many communication applications allow for real-time or near
real-time communication that falls outside of the traditional voice
communication associated with wireline and wireless telephone
communications. Chat sessions, instant messaging, Short Message
Service (SMS), video conferencing, are but a few such communication
vehicles. Many of these types of communications have been
well-received by the communicating public, and are expected to
become increasingly popular, particularly in view of the
proliferation of wireless devices and continual technological
breakthroughs.
[0004] In order to implement such technologies, "presence"
technology is used to determine the location, willingness to
communicate, and other parameters relating to real-time or near
real-time communications. Presence technology generally refers to
applications and services that facilitate location and
identification of one or more endpoints to such communication
links. For example, if a user of a wireless, handheld device would
like to initiate an IM session with another IM user, presence
services may be used to present users' willingness to receive IM
messages. Presence services are an integral part of third
generation (3G) wireless networks, and are intended to be employed
across a wide variety of communication devices.
[0005] Current presence service technology includes the concepts of
presentities, presence servers, and watchers. Generally, a
presentity can provide information as to its "presence" (e.g.,
location, willingness to communicate at a certain time or with
certain users, etc.). This information can be collected and
utilized by presence servers, that can notify authorized "watchers"
who are interested in presence information that certain presence
information is available. Watcher applications may be implemented
in wireline and wireless terminals to obtain presence information
from the presence servers about other users. This may come in the
form of a notification, issued to the watcher by the presence
server.
[0006] Conventionally, notifications to users/watchers that a
targeted user/device has become available have been sent as
complete presence information. In other words, there are a number
of different pieces of presence information that are associated
with the totality of the presence information, and original or
updated notifications result in sending all of the presence
information to the notification-subscribing users who are
"watching" for the particular presence information. For example, in
current IETF presence format specifications such as the Common
Profile for Instant Messaging (CPIM) Presence Information Data
Format (PIDF), all presence information is sent regardless of
whether portions of the information being sent are already
available to the watcher. In some environments, such as wireless
environments, sending all of the presence information when only
some portion of the information has changed may not be a favorable
option, as the available bandwidth is typically significantly lower
than in a fixed Internet environment.
[0007] Existing presence specifications do not provide any
indication whether some data received earlier has become invalid.
This can occur where, for example, watchers change filtering
information, presentities change presence authorization levels, and
presence attributes become unavailable on networks. Furthermore,
the existing specifications do not provide versioning information,
which is needed if presence information is delivered using multiple
application protocols, because protocol-specific versioning
mechanisms cannot be used in such instances.
[0008] Accordingly, there is a need in the communications industry
for a more efficient and convenient manner of providing presence
information. The present invention fulfills these and other needs,
and offers other advantages over the prior art.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a system for
communicating partial notifications relating to a presentity's
presence information.
[0010] In accordance with one embodiment of the invention, a method
is provided for communicating presence information between presence
servers and terminals coupled to the presence servers via a
network. The method includes identifying at least one presentity to
which a terminal has requested presence services. A presence
document is created, where the presence document includes presence
information corresponding to the presentity. The presence
information is configured as partial presence information
comprising less than a total of the presence information available
for the presentity. The presence document having the partial
presence information is communicated to the terminal requesting the
presence information.
[0011] In accordance with another embodiment of the invention, a
method is provided for notifying client terminals of presence
information. The method includes creating a presence document for
use by at least one terminal requesting presence information
regarding a presentity. Creating a presence document includes
creating at least one tuple, wherein the tuple includes a version
value indicating a version of the tuple relative to previous
versions of the tuple, and associating presence information with
the tuple, wherein the presence information comprises a subset of
the presentity's complete set of presence information. The presence
document is sent to the client terminal requesting the presence
information, where the version value provided via the tuple is
compared to a current version value stored on the client terminal.
The client terminal is directed to update presence information
associated with the tuple, if the version value provided via the
tuple indicates new presence information is available for that
tuple.
[0012] In accordance with another embodiment of the invention, a
presence awareness system is provided. The system includes at least
one terminal having a watcher application that watches for presence
information corresponding to a presentity. At least one presence
server is provided, which is coupled to the terminal via a network.
The presence server includes a processor configured to identify at
least one presentity to which the watcher application has requested
presence services. Via the processor (and other computing
elements), a presence document including the presence information
corresponding to the presentity is provided. The presence
information is configured as partial presence information having
less than the total of the presence information available for the
presentity. The presence document having the partial presence
information is communicated to the watcher application of the
terminal requesting the presence information.
[0013] In accordance with another embodiment of the invention, a
presence server is provided, where the presence server is coupled
to a plurality of terminals via a network. The presence server
communicates presence information to one or more of the plurality
of terminals via the network. The presence server includes a memory
configured to store presence information for a plurality of
presentities, and to store terminal subscriptions for terminals
authorized to receive the presence information for one or more of
the presentities. A processing system is provided with the presence
server, and is configured to identify at least one presentity to
which a particular terminal has subscribed, and to create a
presence document including the presence information corresponding
to the presentity, where the presence information is configured as
partial presence information corresponding to a subset of a set of
presence information available for the presentity. A data
transmission module is coupled to the processing system to
communicate the partial presence information via the presence
document to the subscribing terminal over the network.
[0014] The above summary of the present invention is not intended
to describe each illustrated embodiment or implementation of the
present invention. This is the purpose of the figures and the
associated discussion which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The invention is described in connection with the
embodiments illustrated in the following diagrams.
[0016] FIG. 1 is a block diagram illustrating a representative
presence service system in which the principles of the present
invention are applicable;
[0017] FIG. 2 illustrates a representative messaging flow that may
be used in connection with the present invention;
[0018] FIG. 3 illustrates a representative namespace extension
facilitating the use of partial notifications in accordance with
the principles of the present invention;
[0019] FIG. 4 illustrates a representative program segment
implementing one embodiment of the namespace extension in
accordance with the present invention;
[0020] FIG. 5 is a flow diagram illustrating an exemplary
embodiment for providing partial notifications to a watcher
application in accordance with the invention;
[0021] FIG. 6 is a flow diagram illustrating an exemplary
embodiment of a method for processing presence information received
at a client device in accordance with the present invention;
[0022] FIG. 7 is a flow diagram illustrating an exemplary
embodiment of a method for communicating information between
presence servers and terminals coupled to the presence servers via
a network, independent of any particular interface format;
[0023] FIG. 8 illustrates an example of a representative mobile
terminal computing system capable of carrying out operations in
accordance with the invention; and
[0024] FIG. 9 illustrates an example of a representative computing
system capable of supplying presence information in accordance with
the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0025] A portion of the disclosure of this patent document contains
material which is subject to copyright protection. The copyright
owner has no objection to the reproduction of the patent document
or the patent disclosure, as it appears in the Patent and Trademark
Office patent file or records, but otherwise reserves all
copyrights and associated copyright ownership privileges.
[0026] In the following description of the exemplary embodiment,
reference is made to the accompanying drawings which form a part
hereof, and in which is shown by way of illustration the specific
embodiment in which the invention may be practiced. It is to be
understood that other embodiments may be utilized, as structural
and operational changes may be made without departing from the
scope of the present invention.
[0027] Generally, the present invention provides a manner for
communicating presence information. Presence information is created
at a presence server or associated system, where the presence
information is configured as partial presence information that
includes less than all of the status information relating to the
presentity. In this manner, presence information that has already
been transferred to a watcher application need not be unnecessarily
transmitted from presence servers to client watcher
applications.
[0028] A number of entities are generally implemented in a presence
service architecture. A presentity is an entity that provides
presence information. Another entity is a presence server, which
receives presence information from presentities. A watcher is an
entity that is interested in presence information. A representative
embodiment of a presence service architecture is shown in FIG.
1.
[0029] FIG. 1 is a block diagram illustrating a representative
presence service system 100 in which the principles of the present
invention are applicable. In the illustrated embodiment, the
presence service system 100 is implemented as an IP multimedia
subsystems (IMS) network, where watcher and presentity presence
proxy functionalities are mapped to IMS network elements when
located within the IMS.
[0030] The presence server 102 manages presence information
provided by one or more presence suppliers 104, such as presence
user agents and external presence agents, as well as presence
information provided by the network (i.e., location information).
The presence server 102 combines presence-related information for a
particular presentity from the information it receives from
multiple presence suppliers 104 into a single presence document,
based on presence attributes and policies defined in the presence
server 102. Users can then make subscription requests for presence
information available at the presence server 102. As described more
fully below, the users, acting as watchers, can make subscription
requests for receiving the presence information available from the
presentity at the presence server 102. The presentity can also make
a subscription request for receiving the information about the
watchers that had subscribed to its presence information in the
presence server 102.
[0031] The Home Subscriber Server (HSS) 106 serves as a master
database and manages information relating to the mobile subscriber,
such as user profile information. The HSS 106 may support a
subscription profile that identifies information for a given
subscriber such as user identities, subscribed services and
profiles, service-specific information, mobility management
information, authorization information, and the like. The HSS 106
is analogous to the second generation (2G) Home Location Register
(HLR), but also includes information such as location information
that can be used to develop location-based services. Third
generation (3G) HLRs are a subset of the HSS 106.
[0032] The presence service system 100 also includes watcher
applications, such as watcher applications 108 and 110. Watcher
applications are entities that request and/or subscribe to presence
information relating to one or more presentities. When a watcher
application intends to access some presence information of a
presentity, it obtains the address (e.g., SIP URL) where the
request is targeted, and the presence server containing this
presence information can therefore be found via the network. The
presentity presence proxy 112 assists in this regard, as it
determines the identity of the presence server 102 associated with
a particular presentity. Further, the watcher presence proxy 114
performs (among other things) address resolution and identification
of target networks associated with a presentity. Other functions of
the watcher presence proxy 114 and presentity presence proxy 112
depend on, for example, the relative location and trust relations
of the watcher application 108 and the presence server 102.
[0033] Each of the proxies 112, 114 may include various Call State
Control Function (CSCF) modules. The watcher presence proxy 114
includes a proxy CSCF (P-CSCF) 116, and a serving CSCF (S-CSCF)
118. The S-CSCF 118 performs and/or assists in performing a number
of functions, including controlling sessions for the user
equipment/watcher application, obtaining the address of CSCFs in
the presentity presence proxy 112 and of the P-CSCF 116, forwarding
SIP requests/responses to and from the presentity presence proxy
112, triggering and executing services, authentication, etc. The
P-CSCF 116 serves as the point of contact for the watcher
application 108, and performs and/or assists in performing
functions such as translation, security, authorization, etc. The
presentity presence proxy 112 also includes an S-CSCF 120, as well
as an interrogating CSCF (I-CSCF) 122. The I-CSCF 122 serves as a
point of contact in the home network for connections destined to a
subscriber of that home network or roaming subscribers currently
located within that network's service area. The I-CSCF 122 performs
a number of functions, including assigning a serving CSCF 120 to a
user performing registration, contacting the HSS 106 to obtain the
S-CSCF 120 address, and forwarding SIP requests/responses to the
S-CSCF 120.
[0034] In the system 100 of FIG. 1, there are two alternative
locations for watcher applications in an IMS network. A first
watcher application 108 may be located within a User Equipment (UE)
terminal registered in the network. In the illustrated embodiment,
the watcher application 108 can register with the network by
registering to the S-CSCF 118 via the P-CSCF 116, such as is
specified in standard IMS procedures. Another watcher application
110 may be associated with an application server 124 behind an ISC
interface 126 which is described more fully below. The application
server 124 may be used to augment the watcher presence proxy 114
functionality, by allowing a watcher application 110 to subscribe
to several presentities using a single subscription request.
[0035] The presence service system 100 includes a number of IMS
interfaces, which implement the Session Initiation Protocol (SIP)
in one embodiment. The IMS interfaces associated with the
illustrated architecture are referred to as reference points. A
reference point P.sub.X, depicted on interface line 128, represents
the interface between a presentity presence proxy 112 and a Home
Subscriber Server (HSS) 106. This interface assists in the location
of the presence server 102 of the presentity. This particular
reference point P.sub.X is a C.sub.X interface, as a C.sub.X
interface supports information transfer between CSCFs and the HSS
106. The HSS manages location information (among other things), and
the C.sub.X interface thus supports the transfer of at least
location information between the HSS 106, and the I-CSCF 122 and
S-CSCF 120.
[0036] Another reference point P.sub.w, depicted on interface
segments 130A, 130B, and 130C, represents the interface between
watcher application 108 and the presence server 102. This interface
allows a watcher application to request and obtain presence
information. In one embodiment of the invention, this interface is
compliant with Common Profile for Instant Messaging (CPIM)
specifications using the Presence Information Data Format (PIDF),
and may be implemented using SIP for example. A first interface
segment 130A of P.sub.w is a G.sub.m interface, which allows the
watcher application 108 to communicate with the P-CSCF 116. A
second interface segment 130B of P.sub.w is a M.sub.w interface,
which allows CSCFs to interface with one another. The M.sub.w
interface therefore facilitates communication between the S-CSCF
118 of the watcher presence proxy 114 with the I-CSCF 122 of the
presentity presence proxy 112. Another interface segment 130C of
P.sub.w is an IMS Service Control Interface (ISC) which is a
reference point between a CSCF and a server. The ISC interface thus
allows the S-CSCF 120 to communicate with the presence server 102.
Alternatively, the watcher presence proxy 114 S-CSCF 118 may
directly communicate with another watcher application 110 via an
ISC interface 126.
[0037] When a watcher application 108 requests presence
information, this can be accomplished using, for example, the CPIM
PIDF interface definition. A request for information is transmitted
from, for example, the watcher application 108 to the presence
server 102. If the presence server 102 authorizes the subscription,
presence notifications are permitted to be sent back to the watcher
application 108. These notifications may be repeatedly sent to each
subscribing watcher application each time the state of the
presentity changes.
[0038] FIG. 2 illustrates a representative messaging flow 200 that
may be used in connection with the present invention. The messaging
flow 200 describes a representative example of how a watcher can
obtain presence information for one or more presentities. The
example illustrates a number of network elements, networks, and
standards that are part of the IMS domain 201, including a User
Equipment (UE) terminal 202, a Radio Access Network (RAN) 204, a
General Packet Radio Service (GPRS)/Dynamic Host Configuration
Protocol (DHCP) entity 206, a P-CSCF 208, a presence server 210,
and a Domain Name Server (DNS) 212. The UE 202 represents a
device(s) that may include a watcher application that is desirous
of obtaining presence information. The RAN 204 is a 3G network that
provides mobile access to a number of core networks of both mobile
and fixed origin--it is the network that bridges the radio link and
the IP core network.
[0039] The GPRS/DHCP 206 represents exemplary communications
standards that may be used in the IMS domain 201. GPRS is a
packet-switched wireless communication standard for Global System
for Mobile Communications (GSM) that mirrors the Internet model and
enables seamless transition towards 3G networks. GPRS provides
actual packet radio access for mobile GSM and time-division
multiple access (TDMA) users, and is ideal for Wireless Application
Protocol (WAP) services. However, any appropriate IP-connectivity
network could be implemented other than GPRS. DHCP is an IP
addressing discovery methodology that provides a mechanism through
which devices, such as the UE 202, can obtain TCP/IP configuration
settings automatically through the network. The UE 202 can contact
a DHCP server by broadcasting a request packet on the RAN 204 to
obtain its configuration parameters. The DHCP server allocates an
IP address to the UE 202, and provides certain parameters. These IP
addresses and configuration parameters are leased to the UE 202
rather than being statically assigned as in the case of static IP
addressing, thereby reducing the work required to administer a
large network. The DHCP, apart from providing the IP address for
the UE, can also provide the IP address of the P-CSCF that is the
first network entity that the UE contacts for accessing the IMS
core network. The DNS 212 represents a name server that resolves a
logical name (Fully-Qualified Domain Name; FQDN) into an IP
address(es) of the corresponding Internet address. Other IP
addressing discovery methodologies other than DHCP may also be
used.
[0040] A SUBSCRIBE request depicted on path 214 is provided from a
watcher application in the UE 202 to the P-CSCF 210, via the RAN
204 and GPRS/DHCP 206 address discovery. The SUBSCRIBE request is
used to express the watcher application's interest in the target
presentity's presence information, and thus identifies the target
presentity in the request URI. The P-CSCF 208 forwards the
SUBSCRIBE request to the presence server 210, as illustrated by
path 216. The presence server 210 receives the request, and
authorizes (and in some cases may also authenticate) the
subscription. If the subscription is authorized, the presence
server 210 responds by providing a return code of OK shown on path
218, which in turn is forwarded by the P-CSCF 208 to the UE 202 as
shown on path 220. At this point, the UE 202 is watching for
presence information from the target presentity.
[0041] A NOTIFY message shown on path 222 is sent by the presence
server 210 to the P-CSCF 208, and then on to the UE 202 via the
P-CSCF 208 as shown on path 224, in order to propagate the presence
information of the target presentity. This information includes the
state of the presentity and of the subscription. The NOTIFY message
thus informs the watcher in the UE 202 when the presence
information of the presentity to which it has subscriptions has
been initiated or has subsequently changed. If the presence
information was received and processed correctly, the UE 202
responds with an OK message shown on path 226, which is received
and forwarded on path 228 to the presence server 210.
[0042] In accordance with conventional presence specifications and
practices, the NOTIFY messages will include all presence
information relating to the presentity or presentities to which the
UE 202 has subscribed. For example, the existing CPIM PIDF
specification specifies that the entire presence information is to
be sent each time a NOTIFY message is sent. This, however, may not
be desirable or practical in some environments, such as wireless
networks. In such environments, sending the complete presence
document when only some part of the document has changed is
undesirable, largely due to the relatively limited bandwidth in
wireless environments. The present invention solves this problem,
and mitigates the superfluous transfer of presence information that
is already available at the UE watchers.
[0043] In accordance with the present invention, presence servers
provide partial notifications regarding the presentity's presence
state. UE such as mobile terminals can receive these partial
notifications. While presence information includes the presentity's
communication means, the presentity's ability and willingness to
communicate, and other attributes, only changed portions of this
information is sent, thereby minimizing valuable bandwidth
consumption. The present invention provides an extension to current
notification specifications and any analogous notification
practices, by providing for the use of partial presence
notifications. The invention provides for the ability to indicate
that only a portion of the presence information that has been
previously received is no longer valid, and also provides better
support for presence information versioning.
[0044] In one embodiment of the invention, currently existing
presence specifications can still be used to provide the bulk of
the presence information. Thus, all current parsers and
specifications can be used, as the present invention provides an
extension to existing specifications. The extension can be defined
in a manner that it does not cause interoperability problems with
presence implementations that do not recognize the extension. The
invention also facilitates versioning, as one embodiment of the
invention provides its own versioning support. This provides
independence of application level protocols used to transport
presence documents.
[0045] The present invention is described in connection with IMS,
SIP, and the CPIM PIDF specification
(draft-ieft-impp-cpim-pdif-05.txt; incorporated herein in its
entirety) in order to facilitate an understanding of the invention.
It will become readily apparent to those skilled in the art from
the description provided herein that while the present invention is
described in terms of an existing presence specification, namely
the CPIM PIDF specification, the present invention is equally
applicable to other presence information data formats.
[0046] FIG. 3 illustrates a representative namespace extension
facilitating the use of partial notifications in accordance with
the principles of the present invention. The representative
namespace extension is depicted in the form of a table for purposes
of facilitating an understanding of various elements and attributes
associated with such an extension, and the tabular form is not
intended to represent any particular data structure associated with
such information. Further, the representative namespace extension
is described in the context of IMS as an extension to the CPIM PIDF
using eXtensible Markup Language (XML). However, the principles
described herein can similarly be applied to analogous systems,
presence information data formats, and programming languages.
[0047] In the exemplary embodiment of FIG. 3, the extension
namespace includes various elements, including a version 300,
action 308, and mode 310. The version element 300 can be used to
identify the version of the entire presence document, or a single
presence tuple. When used at the presence document level 302, the
version parameter can provide versioning support across different
application protocols, such as SIP, HTTP, etc. When used at the
tuple level 304, the version parameter provides information to the
watcher indicating whether the particular tuple should be updated
or not. A particular example of the use of the version element,
both at the document and tuple level, is subsequently provided in
connection with FIG. 4.
[0048] The action element 306 can be used within a tuple to
indicate an action to be taken by the client on that particular
tuple. Representative values associated with the action element 306
include the removed 308, and empty 310 values. For example, the
removed 308 value may indicate that the presence server no longer
has the particular presence information for this tuple for whatever
reason, and the client can ignore or remove the information
associated with this tuple. The empty 310 value may indicate that
the client is to empty the currently-stored presence information
corresponding to that tuple. Any other 312 desired value can also
be used to correspond to desired actions 306.
[0049] The mode attribute element 314 can be used at the document
level to indicate whether the notification is for an update of a
portion of the presence information, or whether the notification is
to provide a complete presence state. Furthermore, attributes
having standard values may be provided. To provide common behavior
in the UE and to facilitate interoperability, a set of well-defined
values (e.g., No_change, No_value, etc.) may be standardized as
part of the extension namespace. For example, a No_change attribute
can be used to indicate that the client should retain its current
value that it previously received. A No_value attribute can be used
to indicate that the element is available for the client, but the
presence server cannot currently provide a value for it. An example
of how such standard attribute values may be used is described in
connection with FIG. 4 below.
[0050] Using the extension namespace and associated elements
described above, notifications can be provided including only
partial presence information updates. Additional, fewer, or
different elements and attributes may also be associated with the
partial notification extension of the present invention.
[0051] FIG. 4 illustrates a representative program segment 400
implementing one embodiment of the namespace extension in
accordance with the present invention. The representative program
segment is described in terms of eXtensible Markup Language (XML)
to illustrate an exemplary manner in which the principles of the
present invention may be implemented. However, those skilled in the
art will appreciate from the description provided herein that other
programming languages may be used to implement such functions.
[0052] The programming segment 400 includes the XML processing
instruction and encoding declaration 402. The body of the
representative XML document includes the root presence element 404.
This element 404 includes at least one tuple element and extension
elements from other namespaces, described more fully below. The
presence element 404 includes namespace declarations, including the
namespace declaration 408 to indicate the namespace on which the
presence document is based. The namespace declarations can include
other namespace declarations for the extensions used. In the
illustrated embodiment, two other namespace declarations 410, 412
are provided for the extensions used. Namespace declaration 410
relates to instant messaging, and namespace declaration 412 relates
to the partial notification extension in accordance with the
present invention, and is named "PE" (i.e., Presence Extension) in
the illustrated embodiment. The presence element 404 also includes
an entity attribute 414. Presence information is identified by a
presentity or "pres" URL of the presentity. The value of the entity
attribute 414 is the "pres" URL of the presentity that is
publishing the presence document, which in the illustrated
embodiment is someone@example.com.
[0053] In accordance with the present invention, a version element
416 is provided at the presence document level. The version element
416 can be used to identify the version of the entire presence
document, where the associated version parameter 418 provides
versioning support across application protocols. For example, if
the presence document has a version parameter 418 of "3,"this
indicates that the notification is the third notification in that
particular subscription. The client/watcher will have a stored
version parameter that can be compared to the version parameter
418. This can be used to determine whether all tuples should be
obtained from the presence server, rather than only those that
might be designated specifically in the otherwise partial
notification. For example, if the version parameter 418 has a value
that is greater than the value stored at the client by two or more,
this would indicate that the client has fallen out of
synchronization with the presence server. In such a case, the
client should fetch all presence tuples from the presence
server.
[0054] Version elements may also be used at the tuple level, such
that version parameters are provided within one or more individual
presence tuples. The version element 420, which is structured
within tuple element 422, includes a version parameter provided
with the presence information. In this example, the version
parameter has a value of "2." When used at the tuple level, the
version parameter provides information to the watcher indicating
whether or not the tuple should be updated. For example, the tuple
422 having an identification, id="mobile-im," includes the version
element 420 having a version number 424 of "2." If this version
number is higher than an existing version number stored at the
client device, then the client should update this tuple, because
the higher version number 424 indicates that this is a new version
of information for this tuple (i.e., the information has
changed).
[0055] In one embodiment of the invention where the CPIM
specification and PIDF presence data format is utilized, the
presence element 404 will include at least one tuple that contains
a status element. Tuple 422 in FIG. 4 includes such a status
element 426. The status element 426 provides certain presence
status information, and the illustrated status element 426 includes
a basic element 428, of which the values "open" and "closed" may be
specified. These values stand for availability of receiving instant
messages if the tuple is for an instant messaging address, which is
the case for the exemplary tuple 422. In the illustrated
embodiment, the value "open" 430 is value for the basic element
428, indicating that the presentity is available for receiving
instant messages. The presence element 404 may include other
elements, such as the contact element 432, which includes a URL of
the contact address. The contact element 432 may include an
attribute such as the "priority" attribute 434 that identifies a
relative priority of the contact address over the others.
[0056] Other tuples may also be provided in the presence element
404, such as the tuple 436 having an identification, "id=call".
Within this tuple 436 is another element 438, which is an action
element 438 in accordance with the present invention. The action
element 438, labeled "PE:action," indicates the action(s) the
client should perform on the particular tuple 436. The particular
value associated with the illustrated action element 438 is
"removed" 440, which in accordance with one embodiment of the
invention indicates to the client that the call tuple no longer has
an associated value for whatever reason, and the client can ignore,
remove, etc. the value. Any number of different predetermined
actions may be associated with such an action element in accordance
with the present invention.
[0057] The representative presence element 404 also includes a mode
element 442. As previously described, a mode element in accordance
with the present invention may be used at the document level to
indicate that the presence notification is for an update of a
portion of the presence information (i.e., a "partial
notification"), or whether the notification is to provide a
complete presence state. In the illustrated embodiment, the value
associated with the mode element 442 is an "update" value 444,
indicating a partial notification. As previously indicated, a set
of well-defined values (e.g., No_change, No_value, etc.) may be
standardized as part of the extension namespace to provide common
behavior in the UE and to facilitate interoperability. As an
example of how such standard attribute values may be used, a
presence element may include a tuple element, which in turn
includes one or more attributes selected from a set of well-defined
attribute values. The representative code segment below is an
example of how such standard attribute values may be used.
1 <presence> <tuple id="886647846"> <attribute_1>
value_1 </attribute_1> <attribute_2) value_2
</attribute 2> </tuple> </presence>
[0058] In this example, the UE already has presence information
including attribute.sub.--1 having a value of "value.sub.--1" and
attribute.sub.--2 having a value of "value.sub.--2." When receiving
a subsequent notification, the attributes may be changed in a
manner as follows:
2 <presence> <tuple id="886647846"> <attribute_1>
value_new </attribute_1> <attribute_2) no_change
</attribute_2> </tuple> </presence>
[0059] As can be seen, the UE can clearly interpret that the
attribute.sub.--1 has a new value, and that the UE should retain
its current value for attribute.sub.--2 because an easily
recognized standard value of "no_change" has been assigned to
attribute.sub.--2.
[0060] FIG. 5 is a flow diagram illustrating an embodiment of a
method for providing partial notifications to a watcher application
in accordance with the present invention. Namespace declarations
are created 500, including at least one extension namespace
declaration for element types and attributes associated with
partial notifications. A document-level version may be identified
502, to enable the client/watcher to determine, for example,
whether it is in synchronization with the presence server. A mode
may be identified 504, to indicate, for example, whether the
presence notification provides a complete presence state or whether
the presence notification is a partial update. One or more tuples
are created 506. A tuple-level version may be identified 508 for
any of these one or more tuples. An action(s) may also be
identified 510 for one or more of the created tuples. When the
presence document has been created, it can be sent to the
appropriate watcher application in any desired manner. For example,
in one embodiment of the invention, the presence document is sent
to a subscribing watcher application when the associated presence
information changes. Other manners, such as watcher event-triggered
fetching and/or interval polling, may be used.
[0061] FIG. 6 is a flow diagram illustrating an exemplary
embodiment of a method for processing presence information received
at a client device in accordance with the present invention. The
presence notification is received 600, where the presence
notification may be created at a presence server or other entity in
a manner such as that described in connection with FIG. 5. If a
document level version is included in the presence information as
determined at decision block 602, it is determined 604 whether the
document level version indicates that the client is in
synchronization with the presence server. In one embodiment of the
invention, this is determined by comparing the document-level
version with a stored value at the client, and if the document
level version is greater than the client value by two or more, the
client has lost synchronization with the presence server. In such a
case, all of the presence tuples are requested 606 from the
presence server.
[0062] If a mode is provided with the presence information as
determined at decision block 608, it is determined 610 whether the
mode indicates if a partial update is to be performed. If not, the
complete presence state is updated 612. Otherwise, in the case of a
partial update, one or more tuples may include a version value.
Whether a tuple includes a tuple-level version is determined at
decision block 614. If the tuple includes a tuple-level version
value in accordance with the present invention, it is determined
616 whether the version has changed, which in one embodiment is
ascertained by determining whether the client version is equal to
the tuple-level version provided with the presence information. If
the values are equal, then no change of presence information has
occurred over what the client already knows, and the tuple is not
updated 618. Otherwise, the tuple is updated 620. For any of the
tuples, it may also be determined 622 whether the particular tuple
includes an action in accordance with the present invention. If so,
the action(s) is performed 624.
[0063] The present invention may be used in connection with
different interface data formats, protocols, etc. FIG. 7 is a flow
diagram illustrating an exemplary embodiment of a method for
communicating information between presence servers and terminals
coupled to the presence servers via a network, independent of any
particular interface format. At least one presentity to which a
terminal/watcher has requested presence services is identified 700.
A presence document is created 702, where the presence document
includes presence information corresponding to the presentity. The
presence information is configured 704 as partial presence
information including less than the totality of the presence
information available for that presentity. The presence document,
including the partial presence information, is communicated 706 to
the terminal(s) that requested the presence information.
[0064] The terminals having the watcher applications described in
connection with the present invention may be any number of
terminals, including desktop/personal computers, workstations,
large-scale computing terminals, wireless terminals, or any other
computing device capable of executing presence awareness
applications. The wireless terminals include devices such as
wireless/cellular telephones, personal digital assistants (PDAs),
or other wireless handsets, as well as portable computing devices.
The mobile terminals utilize computing components to control and
manage the conventional device activity as well as the
functionality provided by the present invention. Hardware,
firmware, software or a combination thereof may be used to perform
the various watcher application functions and associated features
as described herein. For purposes of illustration and not of
limitation, an example of a representative mobile terminal
computing system capable of carrying out operations in accordance
with the invention is illustrated in FIG. 8. It should be
recognized, however, that the principles of the present invention
are equally applicable to standard computing systems.
[0065] The exemplary mobile computing arrangement 800 suitable for
performing the watcher application functions in accordance with the
present invention includes a processing/control unit 802, such as a
microprocessor, reduced instruction set computer (RISC), or other
central processing module. The processing unit 802 need not be a
single device, and may include one or more processors. For example,
the processing unit 802 may include a master processor and
associated slave processors coupled to communicate with the master
processor.
[0066] The processing unit 802 controls the basic functions of the
mobile terminal as dictated by programs available in the
storage/memory 804. Thus, the processing unit 802 executes the
functions associated with the watcher functions and associated
features of the present invention. More particularly, the
storage/memory 804 may include an operating system and program
modules for carrying out functions and applications on the mobile
terminal. For example, the program storage may include one or more
of read-only memory (ROM), flash ROM, programmable and/or erasable
ROM, random access memory (RAM), subscriber interface module (SIM),
wireless interface module (WIM), smart card, or other removable
memory device, etc. The program modules and associated features may
also be transmitted to the mobile computing arrangement 800 via
data signals, such as being downloaded electronically via a
network, such as the Internet.
[0067] One of the programs that may be stored in the storage/memory
804 is a watcher program 806. As previously described, the watcher
program 806 can fetch and/or subscribe to presence information of
one or more presentities. The watcher 806 and associated features
may be implemented in software and/or firmware operable by way of
the processor 802. The program storage/memory 804 may also be used
to store data 808, such as the various document and tuple version
values, or other data associated with the present invention. In one
embodiment of the invention, the programs 806 and data 808 are
stored in non-volatile electrically-erasable, programmable ROM
(EEPROM), flash ROM, etc. so that the information is not lost upon
power down of the mobile terminal 800.
[0068] The processor 802 is also coupled to user interface 810
elements associated with the mobile terminal. The user interface
810 of the mobile terminal may include, for example, a display 812
such as a liquid crystal display, a keypad 814, speaker 816, and
microphone 818. These and other user interface components are
coupled to the processor 802 as is known in the art. The keypad 814
includes alpha-numeric keys for performing a variety of functions,
including dialing numbers and executing operations assigned to one
or more keys. Alternatively, other user interface mechanisms may be
employed, such as voice commands, switches, touch pad/screen,
graphical user interface using a pointing device, trackball,
joystick, or any other user interface mechanism.
[0069] The mobile computing arrangement 800 may also include a
digital signal processor (DSP) 820. The DSP 820 may perform a
variety of functions, including analog-to-digital (A/D) conversion,
digital-to-analog (D/A) conversion, speech coding/decoding,
encryption/decryption, error detection and correction, bit stream
translation, filtering, etc. The transceiver 822, generally coupled
to an antenna 824, transmits and receives the radio signals
associated with the wireless device.
[0070] The mobile computing arrangement 800 of FIG. 8 is provided
as a representative example of a computing environment in which the
principles of the present invention may be applied. From the
description provided herein, those skilled in the art will
appreciate that the present invention is equally applicable in a
variety of other currently known and future mobile computing
environments. For example, the watcher application 806 and
associated features, and data 808, may be stored in a variety of
manners, may be operable on a variety of processing devices, and
may be operable in mobile devices having additional, fewer, or
different supporting circuitry and user interface mechanisms. It is
noted that the principles of the present invention are equally
applicable to non-mobile terminals, i.e., landline computing
systems.
[0071] The presence servers or other systems for providing presence
information in connection with the present invention may be any
type of computing device capable of processing and communicating
presence information. The presence servers utilize computing
systems to control and manage the presence awareness activity. An
example of a representative computing system capable of carrying
out operations in accordance with the invention is illustrated in
FIG. 9. Hardware, firmware, software or a combination thereof may
be used to perform the various presence awareness functions and
operations described herein. The computing structure 900 of FIG. 9
is an example computing structure that can be used in connection
with such a presence system.
[0072] The example computing arrangement 900 suitable for
performing the presence activity in accordance with the present
invention includes the presence server 901, which includes a
central processor (CPU) 902 coupled to random access memory (RAM)
904 and read-only memory (ROM) 906. The ROM 906 may also be other
types of storage media to store programs, such as programmable ROM
(PROM), erasable PROM (EPROM), etc. The processor 902 may
communicate with other internal and external components through
input/output (I/O) circuitry 908 and bussing 910, to provide
control signals and the like. The processor 902 carries out a
variety of functions as is known in the art, as dictated by
software and/or firmware instructions.
[0073] The server 901 may also include one or more data storage
devices, including hard and floppy disk drives 912, CD-ROM drives
914, and other hardware capable of reading and/or storing
information such as DVD, etc. In one embodiment, software for
carrying out the partial presence notification operations in
accordance with the present invention may be stored and distributed
on a CD-ROM 916, diskette 918 or other form of media capable of
portably storing information. These storage media may be inserted
into, and read by, devices such as the CD-ROM drive 914, the disk
drive 912, etc. The software may also be transmitted to the
presence server 901 via data signals, such as being downloaded
electronically via a network, such as the Internet. The server 901
is coupled to a display 920, which may be any type of known display
or presentation screen, such as LCD displays, plasma display,
cathode ray tubes (CRT), etc. A user input interface 922 is
provided, including one or more user interface mechanisms such as a
mouse, keyboard, microphone, touch pad, touch screen,
voice-recognition system, etc.
[0074] The server 901 is coupled to other computing devices, such
as the landline and/or wireless terminals and associated watcher
applications, via a network. The server may be part of a larger
network configuration as in a global area network (GAN) such as the
Internet 928, which allows ultimate connection to the various
landline and/or mobile client/watcher devices.
[0075] Using the description provided herein, the invention may be
implemented as a machine, process, or article of manufacture by
using standard programming and/or engineering techniques to produce
programming software, firmware, hardware or any combination
thereof.
[0076] Any resulting program(s), having computer-readable program
code, may be embodied on one or more computer-usable media such as
resident memory devices, smart cards or other removable memory
devices, or transmitting devices, thereby making a computer program
product or article of manufacture according to the invention. As
such, the terms "article of manufacture" and "computer program
product" as used herein are intended to encompass a computer
program that exists permanently or temporarily on any
computer-usable medium or in any transmitting medium which
transmits such a program.
[0077] As indicated above, memory/storage devices include, but are
not limited to, disks, optical disks, removable memory devices such
as smart cards, SIMs, WIMs, semiconductor memories such as RAM,
ROM, PROMS, etc. Transmitting mediums include, but are not limited
to, transmissions via wireless/radio wave communication networks,
the Internet, intranets, telephone/modem-based network
communication, hard-wired/cabled communication network, satellite
communication, and other stationary or mobile network
systems/communication links.
[0078] From the description provided herein, those skilled in the
art are readily able to combine software created as described with
appropriate general purpose or special purpose computer hardware to
create a mobile computer system and/or computer subcomponents
embodying the invention, and to create a mobile computer system
and/or computer subcomponents for carrying out the method of the
invention.
[0079] The foregoing description of the exemplary embodiment of the
invention has been presented for the purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise form disclosed. Many modifications and
variations are possible in light of the above teaching. It is
intended that the scope of the invention not be limited with these
illustrated embodiments, but rather the scope of the invention may
be ascertained from the claims appended hereto.
* * * * *